JP3280914B2 - Light shielding sheet for crop cultivation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding sheet for growing crops such as shiitake mushrooms, tea, etc., which not only has adequate moisture and good ventilation but also has an upward It is an object of the present invention to provide a plant-growing light-shielding material that can sufficiently exhibit the function as a light-shielding material without winding around.

[0002]

2. Description of the Related Art Conventionally, as a light-shielding sheet for cultivating crops for this use, a light-shielding sheet for cultivating crops described in JP-B-55-6326 and JP-B-55-24856 has been known. Has been put to practical use. In these known crop cultivation light-shielding sheets, a large number of resin film tapes 1 as shown in FIG. 4 are arranged, and the upper part of each tape is tied or twisted to form a string, and the lower part is left as a tape. A light-shielding sheet for crop cultivation in which a mesh portion A 'is formed at the upper portion and a lower edge hanging tape bundle portion B is formed at the lower portion by connecting the upper string portions with several stages of warps 2 (see FIG. 4). The central part is omitted). Then, as shown in FIG. 5, these crop cultivation light-shielding sheets are used by being suspended above a cultivated crop while being arranged in parallel with each other at a constant interval. Ordinarily, the light-shielding sheet surface for crop cultivation is hung in the east-west direction. The mesh portion A 'of the light-shielding sheet for crop cultivation is formed by twisting a resin film tape into a string to form a string, and the string is connected by a plurality of warps 2 having a step of about 15 mm. Therefore, there are many large gaps in the mesh portion A '. In particular, light is transmitted in spots from both sides of the connecting portion between the warp yarn 2 and the cord-like tape. When light impinges on the surface of the mesh portion at right angles, about 50% of the light is transmitted in terms of area, and when the light impinges obliquely, the light is transmitted in a so-called tree-sunlight state. As described above, the light-shielding property of the mesh portion A 'is not sufficient, but the mesh portion A' imparts rigidity to the crop cultivation light-shielding sheet. The shape is not stable, and the tape-like films are randomly gathered, so that it becomes difficult to install, store, and distribute the crop cultivation light-shielding sheet. On the other hand, the lower edge hanging tape bundle portion B is a bundle of tapes hanging down from the lower edge of the mesh portion, and the area is expanded several times from the compressed string shape to the tape shape. Not only is it spread out, but also the volume increases several times in volume. Therefore, there is no gap between the tapes for transmitting light linearly, and the light is almost blocked in the lower edge hanging tape bundle B. In addition, since the tape bundle swings due to the wind, the lower edge hanging tape portion B has a volume several times larger, and although the light is almost blocked, the wind resistance is small. Even if the wind is in the direction parallel to the plane, but also in the direction perpendicular to the surface, the wind will pass with low resistance in both the mesh and the hanging tape bundle, ensuring air permeability, and There is little risk of the cultivation light-shielding sheet equipment falling down. In the use of the conventional light-shielding sheet for crop cultivation having such advantages, if the interval between the light-shielding sheets for crop cultivation hanging in parallel can be increased, the required number of light-shielding sheets for crop cultivation can be reduced, and ventilation can be achieved. The character becomes better. However, when the interval between the light-shielding sheets for crop cultivation is widened in this way, when it is midsummer to avoid the most direct sunlight and direct sunlight is applied from a high position, sunlight may be generated between the adjacent hanging tape bundles. A gap that can be directly radiated is generated, and sunlight is directly radiated to reduce the light blocking effect. That is,
In the light-shielding sheet for crop cultivation, achieving air permeability and resource saving reduces light-shielding properties.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a crop cultivation light-shielding sheet which does not decrease the light-shielding property even when the interval between the crop cultivation light-shielding sheets during use is larger than in the conventional use mode. It is intended for.

[0004]

The present inventor has made an effort to improve the structure of the known crop cultivation light-shielding sheet in order to overcome the trade-off between the above-mentioned light-shielding property and economical efficiency (air permeability). Intended. In other words, we first considered lengthening the hanging tape bundle with light-shielding properties, but the bulk expansion effect of this part sharply increased at the lower edge of the knitted fabric, but there was no change in the extended tape bundle, There is little improvement in the effect,
The extended hanging portion of the hanging tape has the disadvantage that it hinders the crop cultivation operation underneath. Then, the present inventor, when forming a tape bundle similar to the lower part on the upper edge of the knitted part, covers this so as to hang down on the side surface of the knitted part, not only improves the light shielding property of the knitted part, but also improves the tape bundle part. By the effect of increasing the volumetric bulk several times as large as the above, it is possible to form an aggregate of tape bundles extending like an eave in the side direction along the upper edge of the knitted portion, so that even if the position of the sun rises, the tape on this upper edge The bundle of bundles and the conventional hanging tape bundle portion can shield light at different positions. The light blocking effect of the two tape bundles having a step and the upper edge tape bundle of the upper stage are spread not only in the vertical direction but also in the horizontal direction, so that the light shielding effect is geometrically increased against direct light from above. In such a situation, the light-shielding property does not decrease even if the interval between the light-shielding sheets for crop cultivation is increased, and by providing the tape bundle portion on the upper edge outside the lower edge of the knitting portion, The invention has been completed.

That is, the present invention comprises the following items. (1) By arranging a large number of synthetic resin tapes in the weft direction and knitting and weaving an intermediate portion of the tape to form a knitted portion,
An upper edge tape bundle portion is formed above an upper edge of the knitted portion, a lower edge hanging tape bundle portion is formed at a lower edge of the knitted portion, and a 1 to 10 mm thick 1 or 10 mm A light-shielding sheet for crop cultivation, comprising a hanging connecting string portion to which two or more strings are fixed. (2) The light-shielding sheet for crop cultivation according to (1), wherein the width of the knitted portion is 30% or less of the length of the resin tape. (3) A height of 10 on the hanging connecting cord portion at the upper edge of the knitting portion.
The crop cultivation method according to (1) or (2), wherein a flap portion having a knitted structure of about 40 mm is formed, and an upper edge tape bundle portion is extended from the knitted structure of the flap. Shading sheet. The light-shielding sheet for cultivating crops according to the present invention basically has a rectangular knitted portion in which a tape is knitted in the middle of the sheet, and a tape bundle portion having a structure in which the tape is extended at upper and lower edges thereof. At the upper edge of the knitting portion, a hanging connecting string portion for hanging the crop cultivation light-shielding sheet is attached.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The light-shielding sheet for cultivating crops of the present invention is
The material is composed of a tape-like film obtained by cutting a synthetic resin film into a slender shape, a synthetic resin yarn for knitting an intermediate knitting portion of each tape-like film, and a hanging connecting cord. The material of the tape-shaped resin film can be used without particular limitation as long as it is a resin film having light-shielding properties and weather resistance. For example, polyolefin resin films such as polyethylene and polypropylene can be suitably used. These resin films are preferably opaque colored films in order to impart light-shielding properties. For coloring, a resin obtained by adding a coloring agent to a resin and forming a film is used.
In particular, black coloring pigments are desirable from the viewpoint of light-shielding properties. Further, a film obtained by plating a film with a metal also has a light shielding effect and can be used. The reflection on the metal plating surface does not become transmitted light. The length of the resin tape is appropriately determined according to the maximum incident light angle at the installation position, the dimensions of the knitting portion, the installation height and the installation interval of the crop cultivation light-shielding sheet, and is usually 500 to 1500 mm in length. Tape can be used. A resin tape having a width of 5 to 20 mm, preferably 7 to 10 mm can be used. If the width is narrow, the tape will be torn by the wind. In addition, it is preferable that the width of the tape-shaped portion increases as the width increases, but it is difficult to manufacture the tape-like portion. As the warp for connecting and binding the resin film in the knitting portion, a synthetic resin yarn or a monofilament having weather resistance can be used. The knitted portions of a large number of resin tapes are divided into several stages at intervals of 10 to 20 mm, and the positions of these stages are connected by a warp parallel to the upper edge of the knitted portions. The tighter the upper and lower intervals of the connected warp rows, the greater the rigidity of the crop cultivation light-shielding sheet and the easier the handling. If the width ratio of the weaving portion is reduced and the tape bundle portion occupies most, it becomes very difficult to store, transport, and install the light-shielding sheet for crop cultivation. If the length of the tape bundle is short, the light-shielding property is reduced. From this viewpoint, at least the width of the knitted portion is at least 5%, preferably at least 10% of the length of the tape.

On the other hand, if the width of the knitting portion is too long, it is necessary to suspend the crop cultivation light-shielding sheet from a high position with a high support when installing the crop cultivation light-shielding sheet.
Therefore, the length of the resin tape is 30% or less, preferably 2% or less.
It is desirable to set it to 0% or less. Further, a hanging connecting string portion provided with one or more strings fixed thereto is provided on the upper edge of the knitted portion of the present invention. The string used for the hanging connection string portion of the present invention is used when fixing the crop cultivation light-shielding sheet to the column, and the entire weight of the crop cultivation light-shielding sheet is supported by the connection string portion. The flap can be provided on the upper edge of the knitted portion by fixing the connecting cord on a parallel line at a distance of 10 to 40 mm, preferably 15 to 30 mm from the upper edge of the knitted portion of the present invention. As the string used for the connecting cord portion, a strong string having a thickness of 1 to 10 mm, preferably 3 to 7 mm, or one or two or more monofilaments twisted can be used. When a flap is provided on the upper edge, the tape bundle portion group bends so that the upper edge flap D of the stitch portion on the thick connecting cord portion protrudes to either side as shown in FIG. Since a large number of tape bundles hang down like a fishing line from a position slightly away from the surface of the knitting portion, the width of blocking the direct sunlight is increased by the aggregate of the upper edge tape bundles. When the wind blows from the right side in the state of FIG. 2, the hanging tape bundle above the knitting part A is blown by the wind and flutters to the left side of the crop cultivation light shielding sheet, and the upper edge flap D of the knitting part.
Is pulled by a number of tape bundles and tilts so that it protrudes downwind. As a result, the flaps D of most of the knitted and woven parts of the large number of light-shielding sheets for crop cultivation are almost inclined in a certain direction according to the direction of the wind. When the flap D is present, the wind smoothly progresses even in the wind where the displacement of the upper edge tape bundle portion to the leeward side is weak.

The invention will be described in more detail with reference to an embodiment shown in the drawings. About 7 mm in width as shown in FIG.
As shown in FIG. 1B, a large number of black polyethylene resin film tapes 1 each having a length of about 750 mm are arranged in parallel, and the tape corresponding to the width of the knitting portion A of 150 mm to 350 mm from above the tape group row. Is twisted to form a string-like portion 1a, and the upper and lower portions of the knitted and woven portion are left in a tape state to form a tape-like portion 1b (a central portion in FIG. 1B is omitted). The light-shielding sheet for crop cultivation of the present invention has a structure in which an upper edge tape bundle C and a lower edge hanging tape bundle B are provided above and below a knitting portion A. In this structure, a knitted or woven part A is formed by connecting and knitting or weaving the string-shaped parts arranged side by side as shown in FIG. When the string-like portions 1a are connected by the warp yarns 2 at the same time, the tape-like portions 1b extending vertically from a number of cord-like tapes of the knitting portion A to the upper and lower edges of the knitting portion are automatically bundled. Thus, an upper edge tape bundle portion and a lower edge hanging tape bundle portion can be formed. The tapes of the upper edge tape bundle portion and the lower edge hanging tape bundle portion are a bundle of tapes whose area and volume are rapidly increased as compared with the volume of the cord-like portion 1a. The bulk of the sheet suddenly expands when shifting to the section. The crop cultivation light-shielding sheet of the present invention is used by hanging the crop cultivation light-shielding sheet by fixing the upper edge of the knitted portion A to a support or a rope stretched over the support. The upper edge of the knitting part A is installed so as to support the entire weight of the crop cultivation light shielding sheet. At this time, it is necessary to use a particularly thick and durable upper edge string 3 for supporting the weight.

In the light-shielding sheet for crop cultivation of FIG.
Along the upper edge 20 mm below the upper edge of the knitting section A, a diameter of 3
Two synthetic resin cords 3 of mm are used side by side as a hanging connecting cord. The two strings 3 are fixed to a rope or the like stretched at a proper interval with a known connecting tool at an appropriate interval, and a light-shielding sheet for crop cultivation is installed. At this time, the total weight of the crop cultivation light-shielding sheet depends on the string 3. As shown in FIG. 3, the light-shielding sheet for crop cultivation hangs the lower edge hanging tape bundle portion B downward in the space above the cultivated crop, and makes the sheet surfaces of many knitted and woven parts A parallel to each other. Install in the upper space. At this time, a wire or a string is stretched between the columns on the periphery of the cultivation place, the lower bent portion of the hanging bracket is inserted and fixed to the upper edge string 3 of the light shielding material, and the upper hook portion is fixed. It is usual to hook the stretched wire or string and suspend the crop cultivation light-shielding sheet on the plant for use. The upper edge tape bundle C of the knitting portion, which is a feature of the present invention, has the same structure as the lower edge hanging tape bundle B before use, but in a state where the knitting portion A is used upright, The direction in which the tape hangs down with respect to the knitting portion A is completely reversed, and the tape has a completely different shape structure. Since the upper edge tape bundle portion C of the light-shielding sheet for cultivation of the present invention cannot hang vertically, it first spreads in the horizontal direction of the tape and then hangs downward. As a result, the aggregate of the bulky upper edge tape bundle portion spreads and hangs down so as to cover the upper edge of the knitted portion A like an eave.

The upper edge tape bundle portion of the present invention changes its shape so as to be swayed by the wind while sufficiently fulfilling the light shielding purpose, so that it has little resistance to the wind, has good air permeability, and has the danger of collapse due to strong wind. The few points have the same properties as the lower edge hanging tape bundle. However, in FIG.
In particular, the structure is such that the weight of the light-shielding sheet for crop cultivation is supported by the string 3 slightly below the upper edge of the knitting portion A. With such a structure, the flap D is formed on the upper edge of the knitted portion A. The flap D is normally tilted to one side depending on the weight of the tape bundle, but when a strong wind blows from the tilted side, the tilt changes in the leeward direction of the knitted portion A as shown in FIG. As shown in FIG. 3 (a) or (b), the light shielding range by one crop cultivation light shielding sheet is expanded by the upper edge tape bundle C which hangs down from the position horizontally projected by the flap D. Moreover, since the direction of the wind acts on the flaps D of the light-shielding sheets for all crop cultivation in a similar manner, the flaps D of the light-shielding sheets for crop cultivation installed in a large number in parallel are inclined in the same direction. Therefore, the upper edge tape bundle C
Thus, a uniform light shielding effect can be obtained without overlapping light shielding ranges. Such an effect of the flap D can be achieved by appropriately selecting the balance between the rigidity of the flap D and the weight of the upper edge tape bundle C. The rigidity of the flap D can be appropriately adjusted by the density of the weave. Further, the light-shielding sheet for cultivating crops of the present invention does not cause the lower edge hanging tape bundle portion B to be entangled with the upper edge tape bundle portion C even when the tape is blown by the wind, and can sufficiently function as a light shielding material.

[0011]

The light-shielding sheet for cultivating crops of the present invention is provided with an upper edge tape bundle so that the light-shielding range per sheet is enlarged while preventing the cultivation work from being hindered. The number of cultivation light-shielding sheets can be reduced, and the air permeability can be improved.

[Brief description of the drawings]

FIG. 1 (a) is a plan view of a resin film tape used for a light-shielding sheet for cultivating crops according to the present invention.
(B) is a top view of an example of the crop cultivation light-shielding sheet of the present invention.

FIG. 2 is a perspective view showing a usage state of a light-shielding sheet for crop cultivation of the present invention.

FIG. 3 is a side view of an upper part of a crop cultivation light-shielding sheet showing a situation in which the shape of a flap at an upper edge of a knitted portion of the crop cultivation light-shielding sheet of the present invention changes.

FIG. 4 is a plan view of a conventional light-shielding sheet for crop cultivation.

FIG. 5 is a side view showing a usage state of a conventional light-shielding sheet for crop cultivation.

[Explanation of symbols]

 Reference Signs List A Weaving part A 'Mesh part B Lower edge hanging tape bundle part C Upper edge tape bundle part D Flap 1 Resin film tape 1a Resin film tape string part 1b Resin film tape tape part 2 Warp 3 String (connection for hanging) String part)

Claims (3)

(57) [Claims] 1. A large number of synthetic resin tapes are arranged in a weft direction,
By knitting an intermediate portion of the tape to form a knitted portion, an upper edge tape bundle portion is formed above an upper edge of the knitted portion, and a lower edge hanging tape bundle portion is formed at a lower edge of the knitted portion. A light-shielding sheet for crop cultivation, wherein a hanging connecting string portion in which one or more strings having a thickness of 1 to 10 mm are fixed to the upper edge of the knitting portion is provided. 2. The width of the knitting part is 30% of the length of the resin tape.
The crop light-shielding sheet according to claim 1, wherein: 3. A flap portion having a knitting structure having a height of 10 to 40 mm is formed on the hanging connecting cord portion at an upper edge of the knitting portion, and an upper edge tape bundle portion is extended from the knitting structure of the flap. The light-shielding sheet for crop cultivation according to claim 1 or 2, wherein: